Oleaginous microorganism is microorganism producing bio-oil using unicellular photosynthetic organisms which may be photo-synthetically grown using water, carbon dioxide, and sunlight or chemicals such as sugar, organic acid, and low molecular alcohol.
The oleaginous microorganism may be cultivated anywhere like a waste land, a coast, and an ocean if there are organic materials which may be photosynthetically grown or may be used as feed and live in freshwater, brackis water, or sea water at a size of 0.5 to 30 μm and contain useful materials such as oil and antioxidant. In particular, the oleaginous microorganism has a good quality of bio-oil accumulated therein and has oil production per unit area at least 10 times higher, at most 100 times higher, and about 50 to 100 times higher than edible plants such as bean and rape plant for obtaining the existing raw oil for bio diesel.
Further, the oleaginous microorganism has a growth rate faster than land plants and may be cultivated in mass production at a high concentration and may be grown even under the extreme environment.
In addition, the oleaginous microorganism demonstrates fuel productivity higher than the existing corps since a usable oil component reaches 30 to 70% of bio mass. Further, the oleaginous microorganism does not compete with other plants in terms of a ground or a space, and therefore does not cause secondary environmental problems such as price increase of food resource and deforestation.
Accordingly, a technology of producing bio-diesel using the oleaginous microorganism has high productivity per unit area to easily secure resources and does not compete with a food resource and thus may be considered to be adequate for domestic circumference in Korea.
Meanwhile, as a method for extracting raw oil for bio-diesel from the oleaginous microorganism, a one-step solvent extraction method has been mostly used. The solvent extraction method separates oil into a solvent phase from the oleaginous microorganism by using an extracted solvent which may dissolve oil from components of the oleaginous microorganism well and has a slight difference in an extraction yield depending on a kind of used solvent but has limited extraction efficiency and extracts a large amount of microorganism bio-element impurities together at the time of extraction of oil to remarkably reduce conversion efficiency into a bio-diesel.
Therefore, technologies of disrupting a cell of oleaginous microorganism using methods such as microwave pre-treatment (Korean Patent Laid-Open Publication No. 2013-0014091), ultrasonic treatment using sonication (Japanese Patent Laid-Open Publication No. 2010-187645), electro beam treatment, plasma treatment, etc., prior to extracting raw oil for bio-diesel from oleaginous microorganism have been well known.
However, in extracting the bio-oil from the oleaginous microorganism by an oleaginous microorganism disruption process based on the technologies, complex processes such as a separate process of removing moisture and a process of giving cooling conditions to cope with occurrence of flames need to be additionally performed and the oleaginous microorganism is denaturalized by heat to cause the degradation in quality of product oil, etc.